Electric furnace for transforming pig-iron into steel.



G. GIN. ELECTRIC FURNACE FOR TRANSFORMING PIG IRON INTO STEEL. APPLICATION FILED JAN. 25, 1906.

970,700, Patented Sept. 20, 1910.

2 SHEETSSHBET 1.

G. GIN.

ELECTRIC FURNACE FOR TRANSPORMING PIG IRON INTO STEEL.

APPLICATION FILED JAN. 25, 1906.

970,?69. Patented Sept. 20, 1910.

2 SHEETS-SHEET 2.

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il mid Mv w Mam In connection with the UNITED STATES PATENT OFFICE.

ensravn GIN, or PARIS, FRANCE, nssrenon TO FRANCIS B.

CROCKER, OF NEW YORK, N. Y.

ELECTRIC FURNACE FOR TRANSFORMING- PIG-IRON INTO STEEL.

' Specification of Letters Patent.

Patented Sept. 20, 1910.

Application filed January 25, 1908. Serial No. 297,855.

-1nt0 steel, and constitutes an improvement upon the furnace for the manufacture of steel forming thesubject matter of Letters Patent Number 771,872, granted to me Octoher 11th, 1904.

In the accompanying like reference letters designate corresponding parts throughout the several views, Figure 1 is a plan view showing fused metal as it appears in One form of channel which I provide in the hearth of my'furnace. Figs. 2, 8 and 4: illustrate in plan view molten metal in channels of other sha e'. Fig. 5 is a longitudinal sectional view 0 a preferred form of my furnace. Figs. 6 and 8 are cross sectional views taken on lines 66 and 88 respectively of Fig. 5, and, Fig. '7 is a horizontal sectional view of the said furnace.

The electric furnace set forth in my Patent Number 771,872 hereinbefore referred to was provided with steel electrodes which might be objectionable if the furnace was used for any other purpose than refining steel, and would be a serious obstacle in case the furnace was used to produce any other metal than iron in a pure state. g

It is the general'purpose of this invention to avoid the use of electrodes, and to employ in lieu thereof means to generate in molten metal contained in one or more endless channels an induced current of electricit In doing this I employ a hearth of suita le refractory material having in the upper sur-. face thereof one or more crucibles of annular form in which the material to be operated upon forms a closed electrical circuit. annular crucibles I employ a magnet having portions thereof extending from without the furnace Within the annular crucible or crucibles. The magdrawing in which net is provided with a suitable primary winding outside of the furnace, and has portions extending above and below each of the annular crucibles, and joined within said crucibles as "illustrated in Figs. 1, 2, 3 and 4. The parts are so arranged that a current of electricity passing through winding or coil will generate an induced current inthemetal in the annular crucibles, this current being transformed into heat in itls passage through the metal in the cruci- In Fig. 1 I have illustrated metal A contained in one form of endless crucible. A' singlemagnet B', provided with the primary winding or coil 0 is employed to generate a current in the metal A, as heretofore described.

In the form of apparatus shown in Fig. 2 the metal A is treated in three elongated parallel endless channe s, disposed as shown. In this form of my invention I employ a magnet B having three arms 6 extending within the separate closed channels, as shown. i

Fig. 3 shows a form of construction in which the metal A is containedin two par allel endless channels. The magnet B has two arms and a single primary coil C, as

shown.

Fig; 4 illustrates a form of my invention in which the metal A is contained within three arallel channels, joined at their ends, as illiistrated. In connection with this form of crucible I employ a magnet B having a double coil provided with similar windings C, but Wound in opposite directions. These windings may be connected in series orparallelas preferred. In this construction, the intensity of the current induced in the central channel will be twice as great as that in the outer channels.

In Figs. 4, 5 6 and 7- I have illustrated a furnace embodying my. invention in practical form.

I have selected for detailed illustration the form of my invention shown in Fig. 3, the construction of a furnace having crucibles of other shapes illustrated will be obvious however from the illustration and description of the form selected.

The furnace contains a hearth of nonconthe primary ducting refractory material which may be inclosed in a suitable metallic frame. In

. vertical chambers D are within the annular channels, so that the magnets encircle the circuits formed by the metal in the channel. The furnace is providedwith a pivotal support at its lower part, as shown. The furnace is tilted or oscillated on this pivotal support by means of screw jack F, which may be driven by hand or by power.

In the production of steel in this furnace,

one may proceed to the smelting and to the oxidation of impurities in one of the channels while the reduction and the carburization are effected in another channel. When the operation is ended, the refined metal is run off through the orifice G, while the orificcs H remaln closed. When the running off is terminated, the orifice G is closed with a plug; and the communicating orifices H are opened. The metal of the first crucible then runs into the second one. The furnace is then brought back to its horizontal position and the first crucible is filled with a quantity of pig-iron and scra iron, equivalent to that which has been ta en out.

It will be observed by reference to the drawings, 6. 9., Fig. 3, that mysaid crucibles or channels are of substantially the same cross sectional area throughout, and, as I have stated, elongated, endless and parallel, and that said crucibles or channels comprise extended portions folded back into parallelism with eachother; also that, as illustrated in Figs. 1, 2, 3. and 4,.the energizing magnet is so disposed relativelyto said parallel portions that parts of latter lie relatively outside of the magnetic influence and so close to each other as to largely reduce self induction and reactance, the distance of said parts from said magnet being much greater than the diameter of the horizontal cross-section of said magnet taken in the plane of said crucible.

Having described my invention, I claim: 1. In an. induction furnace a hearth comprising a horizontally disposed endless crucible 'or channel of substantially the same cross-sectional area throughout, said channel inclosing elongated portions, adjacent one end ofsaid elongated portions an electromagnet adapted to set up an induced electric current in metal contained in said crucible, parts of the said channel being so far elongated from said magnet as to lie relatively outside of the magnetic influence and parallel and so close to each other as to, largely reduce self-induction and reactance.

2. In an induction furnace a hearth comprising a horizontally disposed endless crucible or channel of substantially the same cross-sectional area throughout, and an electromagnet having a part thereof disposed within the space surrounded by said crucible, said crucible comprising portions thereof disposed parallel with each other, and so close to each other as to largely reduce selfinduction and reactance and at a distance from said magnet not less than the diameter of its horizontal cross-section taken in the plane of said crucible.

3. In an induction furnace a hearth comprising a horizontally disposed endless crucible .or channel, of substantially the same cross-sectional area throughout, disposed to encompass two portions of said hearth, and two electro -magnets each having a part thereof disposed within one of said portions of said hearth and each having a coil wound oppositely to the coil of its adjacent electromagnet, whereby the intensity of the current in metal contained in that portion of said crucible extending between said portions of said hearth is greater thanin metal contained in other portions of said crucible.

4. In an induction furnace a heart-h comprising a plurality of horizontally disposed endless crucibles or channels of substantially the same cross-sectional area throughout and said crucibles or channels, each of said crucibles comprising portions parallel with each other and so far elongated from its proximate arm of said magnet as to. lie relatively outside of the magnetic influence and so close to each other as to largely reduce self induction and reaction.

5. In a furnace of the type set forth, a hearth provided with a plurality of endless crucibles or channels inclosin'g a plurality of elongated portions of said hearth, and one or more electro-magnets disposed in juxtapositionto one end ofsaid elongated portions, said electro-ma'gnet or magnets belng provided with one or more energizing coils disposed exteriorly of said crucibles or channels, and said electro-magnet or magnets I -in portions of said hearth inclosed by said crucibles or channels, substantially as de scribed.

6. In a furnace of the type set forth, a hearth provided with a plurality of endless crucibles or channels inclosing a plurality of elongated portions of said hearth, and one or more electro-inagnets having a plurality. extending within the portions of said hearth of juxtaposed cores disposed 1n juxtaposition to one end of said elongated portions, substantially as described.

coils surrounding said cores, said coils being GUSTAVE GIN. oppositely wound on adjacent cores and said electro-magnet or magnets having a plurality of arms connected with said'cores and In presence of.

LOUIS PETITALOT, HANSON C. COKE.

surrounded by said-crucibles or channels 

